Filter structure for suction cleaning apparatus



May 5, 1953 F. A. MARTIN ETAL 2,637,410

FILTER STRUCTURE FOR sucwxon CLEANING APPARATUS Filed April 25, 1951 2SHEETS--SHEET 1 FlG.l

INVENTORS. FRANK A. MARTIN BY M LVIN H. RIPPLE ATT'Y y 5, 3 I F. A.MARTIN ETI'AL 2,637,410

FILTER STRUCTURE FOR SUCTION CLEANING APPARATUS Filed April 25, 1951 2SHEETS-SHEET 2 INVENTORS: FRANK A. MARTIN ELVIN H. RIPPLE ATT'Y PatentedMay 5, 1953 iCiEi FILTER; STRUGTURE FORrSUCTIlDN CLEANING APPARATUSliFrank AflMartin, Akron, and' Melvin'H. Ripple,

Canton; Ohio," ass ignors to The lloover' (Jonip-any, North Ganton,Ghio, a. -.corporation@;of

ApplicationAmtil. 25,. 1951, SerialNo. 222,734

7 Glaims. (Cl. 183 -el) The present invention r'elates "to filterrstructures for use with suction. cleaning apparatuses and in.particularto an arrangement permitting the end of the filter not normallyattachedrtothe suction cleaner exhaust outlet to be simply andefiectively sealed during use of the filter with the cleaner and to openautomatically to its maximum extent when removedirom the. cleane toempty the filter, of accumulated dirt.

It is aparticular object of, our invention to provide .a suctionoleanerfilter sack having emptyingenden'closing a resilient liner member which.is normally hiasedlto open the mouth oi thejfilter. to substantiallyits. maximum extent but whichpositions the partswhen. so opened to foldautomaticallyinto aflat structure by thev application. 01a lightisidewise pressure thereto for reassembly Withthe cleaner.

.Itis a. further. .objectof the present invention to provide. a suctioncleaner. filter each having". a i molded. plastic insert lther'einmolded: to provide two vcomparatively.rigid side rail members connectedbyanair. of leaf members hingedLto the side rails and. each other by.integral hinges. arrangedito anglethe hinge leaves inwardly to-' wardeach other when unstressed so that .sidewise pressure applied to therail-members.causes the hinge leaf members automatically to fold in-Wardlyuintoproper. position. for assemblyof the cleaner mouth in amounting clip.

'It is .a. further object of thepresentinvention ot provide an elastic.material insert for. a suction cleaner bag mouth having an integralhinge construction vlzhichibiases the insert .to a predetermined; open;emptying position but which. readily folds: into aflatcondition withoutimposing excessivestresses upon tie elastic material and withoutcrushing. the...fi1ter. material.

Otherobiects, and..adv.an.tages of the. invention will become I apparentas. the. description proceeds when taken .in. connection. with the.accompanying drawing. in which:

Figure. l is aplan view of -aplastic. insertimeinher for a suctioncleaner andifilter bag;

Figure 2 is a broken view illustrating. the. device of Figure l the flatfolded. condition;

Figures is. a perspective vievvoithe, enml ying end. of a suction.cleanerfilter sack-embodyin the present invention and. positioned, in.the... emptying condition. thereof Figure 4 is a. sectionalovieww taken.alongthe line 4-4 of. Figure 5;.illustrating .the.,.roanner in which theioldedendof; the bag, is secured-in the mounting clip; and

Figure 5 is a broken view illustrating a suction cleaner filterembodying invention andattachedto amounting clip.

Referring now to the drawing indetailand first'to' Figure 1 thereof,there is 'i-l'lustrateda'suo tioncleaner-filter mouth'iramel made ofanelastomeric meter 1. Preferably the frame l is maolded in a go. rallyrectangular-shape of suitable plastic such 1.03"PG1Y811'11Y1BI18. Theframe 1 comprises opposed side rails 2;; and 3 connected to each otherat their left handends,-as viewed-in Figure .1,- by a pair oi-hingeleaves land: i -and atitheir righthandends byasecondpair-of hingc leavesand l. The-hingeleaves l and 5'are hinged together by means of anelongated-"fiat hinge section ll atthe center of the frame i.

Similarlythe hinge leavesf 5- "l are'joined-hy another hinge section 8.""The-side-rails-2and 3 are joined to the hinge leaves lfltol inclusiveat the corners of thegframe-by: elongated fiat-hi-nge sections 9. Thesections llyandfl havea-smaller cross section and are I101,flE3Xlbl(-Ythan thehinge leaves. and side rails; hence the hinging action alwaysoccurs at the sections-8 and fi. "Thefiat hingesections't'are soconnected to the hinge leaf portionsof the frame that theyiorms1nooth=continuations ofzthe inside-surfaces of the hinge leaves andpresent outwardly facin indentation ill. The hinge sections 9" soconnected to the hinge leaves tol inclusive; that they form acontinuation oi the outside surface of the hinge leaves and an inwardlyfacing indentation l l with the inner surfaces of the'h-ingeyleavesandside rails. The siderails are designed to be mo-rerig'id than thehinge leaves lto i and are tl'rereioremade .The, angular relationshipis-not-criticaland the internal angle betweenthe siderails --and thehinge. leaves may lee-fromseventy-toeighty-five degrees, for example.*Eaclrof the side-rails at its. center portion is; provided 'with aninwardly directed .nib ii for apurpose to-he described-"hereinaiter. Theexternal; s-urfaceflof the rail 2 opposite thenio'l his provided with-anelongated indentation .l tto accommodate a bag seam 'to'be describedhereinafter.

Itisapparent fromfiigure l that a light-pressure applied to"theside--rai1s2and 3-tending" to 3 push the same towards each otherwill cause the frame I to fold into the flat condition illustrated inFigure 2.

When the frame is folded, the elongated fiat and narrow hinge sections 8and 9 assume a substantially circular shape as shown in Figure 2 toprovide substantially circular openings at the junction point betweeneach pair of hinge leaves and the junction point between each hinge leafand side rail. As a result of this, the hinge sections of the plasticframe assume an arcuate relationship in which they are stressed about anarc which is within the elastic limits of the par ticular material. Forexample, using polyethylene, the radius of the internal are at thefolded hinges may be as small as one-twentieth of an inch. The openingsthus formed also provide space for filter material as Will be apparentas the description proceeds. In the folded condition of the frame, theprojecting nibs I extend into the space between the now juxtaposed hingesections 8 to aid in forming a seal at this point.

Each of the sections of the frame I is rectangular in cross-section withthe long dimension of the rectangle at right angles to the plane ofFigure 1. Cross-sections of portions of the frame are shown in Figure 4.In the folded condition of the frame, the hinge leaves 4 and 5 arejuxtaposed and in parallel relation to each other and to the side rails2 and 3. Similarly, the hinge leaves 6 and I are juxtaposed in parallelrelationship to each other, to the side rails 2 and 3 and are alignedwith the hinge leaves 4 and 5. The stresses in the hinge sections 8 and9, when the frame is in the folded condition of Figure 2, naturally tendto spring the frame to the open, unstressed condition illustrated inFigure l, which is the shape in which the same is originally molded. Ifthe leaves are moved closer to a right angular relationship with theside rails, that is, away from each other from the position illustratedin Figure 1, the stress in the hinges 8 and 9 tends to return the frameto the condition illustrated in Figure 1. A small space has been shownbetween each juxtaposed portion of the frame in folded condition inFigure 2 to illustrate the space taken up by enclosing filter fabric aswill be apparent from Figures 3 and 4.

Figure 3 illustrates the open end of a suction cleaner filter 20incorporating the frame I and in its relaxed or emptying condition. Theframe I is not visible in Figure 3 as it is covered by the material ofthe filter 20. The reference characters applied to the frame side railsand hinge leaves in Figure 1 are applied to the corresponding parts inFigure 3 in order to locate the frame with reference to the filter 20.Th material of the filter 20 is formed in tubular shape with the edgesoverlapping to form a seam indicated at 2| which is secured by stitching22 to form a tubular body. The tubular filter 20 thus formed ispreferably turned inside out as is the frame I. The tubular body is thentelescoped through the frame and the free end turned down around theframe to cover the same and then stitched to the body of the bag bystitching indicated at 23. The filter 20 and now in-sewn frame is thenturned right side out to produce the structure indicated in Figure 3with the inturned flap 24 of the filter stitched to the body of thefilter on the inside thereof. The filter then presents a tailoredexternal appearance and the tubular body 20 is substantially fiush withthe outside surfaces of the internal frame I. The seam 2I-22 of thefilter 20 is aligned with the inden- 4 tation I6 in the side rail 2 sothat the double thickness of material lies in the indentation, and asmooth continuous external surface is provided at the top of theassembled filter at this point.

When the assembled filter is collapsed to bring the top frame memberinto the condition illustrated in Figure 2, the double thickness offilter material positioned between each juxtaposed hinge leaf pair andhinge leaf side rail pair forms a seal which prevents the escape of dirtand air through the filter mouth. The folding operation causes thematerial on the inside of the filter to bunch or gather at the hinges.The gathered material fills and seals the circular openings formed atthe hinge points when the frame is in folded condition and also providesa shaping form for the hinge sections barring the formation of sharpbends therein. The nibs I5 on the side rails project into and seal thespace left between the hinges 8 when the frame is folded. The presentconstruction provides a completely sealed filter mouth which avoidscrushing or biting of the filter material and which has no relativelymovable mechanical parts positioned internally of the filter material.

The collapsed emptying end of the filter may be slid sideways into aU-shaped sealing and supporting clamp 26 of spring material shown inFigures 4 and 5. The clamp 26 has converging bottom wings 21 which pressthe material of the filter together below the portion thereof encasingthe frame I to form a neat finished appearance and to insure an air anddirt seal at the mouth portion of the filter 20. The space beneath theframe I at the apex of the angularly positioned wings 21 forms amplespace for accommodating the various flap portions 24 of the filtermaterial which are turned over the frame I and are stitched back to thefilter to trap the frame. The spring clip 25 forms a moderately tightfit with the frame encasing portion of the filter so as to press thesame tightly together to form a complete air and dirt seal.therebetween.

The lower portion of the filter is necked in as indicated in Figure 5and is secured to a clamping ring 28 of any desired type which will beutilized for the purpose of securing the lower end of the filter 20 tothe exhaust outlet of a suction cleaner. The spring clip 26 is providedwith a bail section 3I at its top to which a suitable support, such as atape or spring, may be attached for mounting the upper end of the filterfrom a suction cleaner propelling handle in a known manner.

Our invention provides a filter in which the 'upper or emptying mouththereof automatically opens substantially to the full extent provided bythe filter fabric with the hinge leaves angled slightly inwardly toensure proper folding in response to a light pressure on the side railsof the frame. The frame seals completely without crushing the filterfabric or catching the same in mechanical devices, and the filter fabricgathered at the hinges provides a proper radius of curvature for thehinge straps.

We claim:

1. A folding frame for filter sack mouths cornbiased to move saidprincipal members apart until each of said leaves assumes a positionforming an internal angle less than a right angle with the principalmember to which it is directly connected whereby pressure applied to theoutside of said principal members will move said members togetherfolding said leaf members together between said principal members.

2. A filter comprising a tubular body of filtering material having anopen mouth portion, a frame secured to the open mouth portion of saidfilter body comprising a one piece body of plastic material having apair of opposed side frame sections, a thin section elongated fiat hingeportion joined to each end of each of said side frame sections, a hingeleaf member joined to each of said hinge portions, and a thin sectionelongated flat hinge portion joining each pair of hinge leaf membersjoined to corresponding ends of said side members.

3. Apparatus according to claim 2 in which the filter material definingthe open mouth portion of said tubular body is turned over said frame toenclose and conceal the same, and said flat hinge portions are offsetfrom the faces of said side frames and hinge leaf members to definesubstantially circular openings accommodating gathered filter materialwhen said frame is folded with said hinge leaf members folded betweensaid side frames.

4. A device of the character described comprising a frame of elastomericmaterial composed of a pair of opposed side rails, a pair of opposedfolding members each comprising a pair of hinge leaves joined by ahinge, and hinges joining the ends of said folding members to the endsof said side rails to form a polygonal frame in which said hingescomprise elongated flexible sections of said frame having a lessercross-section than said side rails and hinge leaves, the hinges joiningsaid side rails to said folding members are offset outwardly from theinner faces thereof, and the hinges joining the hinge leaves of saidfolding members are offset inwardly from the outer faces thereof wherebymembers joined by a hinge member, hinge memsaid hinge members have asmaller cross-section said hinges assume an arcuate form aroundsubstantially circular openings when said frame is collapsed with thehinge leaves of each of said folding members lying between said siderails in substantially parallel relation to each other and to said siderails.

5. Apparatus according to claim 4 including a tubular filter body havingan open end portion turned back upon itself around said frame to enclosethe same in said filter body.

6. A filter mouth frame comprising a onepiece body of elastomericmaterial including, a pair of opposed rail members, a pair of opposedfolding members each comprising a pair of leaf bers joining the ends ofeach of said folding members to corresponding ends of said rail members,and said hinge members being formed t bias said frame to an openposition in which sai rail members are spaced apart and each of sai leafmembers is spaced from and forms an internal angle less than a rightangle with the rail member to which it is directly hinged. 1 '7.Apparatus according to claim 6 in whic than said leaf members and saidrail members the hinge members joining a principa1 membe to a leafmember are offset outwardly of th inner faces thereof, and the hingemembers joining the leaf members forming said folding members are offsetinwardly from the outer face thereof.

FRANK A. MARTIN.

MELVIN H. RIPPLE.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,513,395 Holmes Oct. 28, 192 1,753,458 Willis Apr. 8, 1931,787,224 White Dec. 30, 193 2,364,069 Hahn Dec. 5, 194 2,503,918'Osborn Apr. 11, 195

